Rumors of a possible trade will follow Alex Smith until March 12 when teams can start making moves.(AP)

There is a reason both general manager Trent Baalke and coach Jim Harbaugh expressed late last week it was a highly unlikely possibility the 49ers would release quarterback Alex Smith.

After being around decision-makers from around the NFL for several days, it became apparent that there would be a trade market for the 49ers' backup quarterback who is still on the books to be the team's highest-paid player in 2013. Also, why would they want to alert teams that a quarterback they might want would soon be released?

It's kind of the same situation with a potential trade. Why would the 49ers decline to continue to negotiate a possible trade two weeks before it can become official?

No trade can be finalized until March 12, 1 p.m. (PT), when the new league year begins. A lot can happen between now and then, and it's unreasonable to think the 49ers have closed the bidding and would turn away a better offer.

But, as of right now, indications point toward a deal happening quickly and Smith becoming the next 49ers-quarterback-turned-member-of-the-Kansas City Chiefs. Jason La Canfora of CBS Sports reported, via Twitter only, the 49ers have "expressed to others that a deal for QB Alex Smith is effectively complete."

There are two main reasons the Chiefs would want Smith on their roster, aside from new coach Andy Reid believing he provides the club with a significant upgrade over Matt Cassel.

The Chiefs own the No. 1 overall pick in the NFL draft. And, not only do they believe there's not a quarterback worthy of the first selection, they're not sure there's a quarterback available who should be chosen in the first round. Period.

"There is no quarterback where personnel guys can definitely say, 'He's a first-round pick,'" Chiefs new general manager John Dorsey recently told The Kansas City Star.

Another big reason that Smith is such an attractive pickup for a team with an unsettled quarterback situation is he's not a jerk.

Smith has shown an ability to adapt to new offenses and new coaching. But he also has a track record of handling backup duties with aplomb and class. If the Chiefs invested a draft pick on a quarterback who eventually supplanted Smith as the starter, they would not have to worry about Smith becoming a problem in the locker room.

In any event, it appears more likely than ever that Smith has played his final game for the 49ers -- for now.

But years from now, when/if Smith gets to the point when he is content in a backup role, it's not out of the question the 49ers would want him back to fill that duty.